Spring powered electric generator



Sept. 26, 1950 G. BOE 2,524,005

SPRING POWERED ELECTRIC GENERATOR Filed May 27, 1948 2 Sheets-Sheet 2 FIG. 6

INVENTOR. GOTTFRED BOE Patented Sept. 26, 1950 SPRING POWERED ELECTRIC GENERATOR Gottfred Boe, Englewood, N. .I., assignor to Specialties, Inc.

Application 'May27 1948 Serial No. 29,549

4 Claims.

The present invention relates to spring powered electric generator units of the type producing for a fraction .of a second a current of predetermined amperage .and voltage.

The invention has been developed more particularly in the production of a generator unit designed "for emergency use .of .airplane pilots to ignite a number of explosivesquibs which initiate the operation of means permitting escape of the pilot from .a pressurized vcockpit. Such an embodiment of the invention will be more particularly described for the purposes .of disclosure of the principles of the invention but it will be understood that the description is illustrative and is not intended as restrictive.

The principalobject of the invention is to provide spring powered generator unit which is reliable and as nearly accident proof as possible in use.

The invention aims to provide a unit, the operation of which can be initiated by the .pilot by a simple movement requiring little effort.

The invention aims further to provide an indicator by which the pilot can readily know whether the spring motor is suitably wound and ready for operation.

Another object is to include provision for automatic operation of a switch to connect the generator to the work .circuit for operation and to restore the circuit to normal condition aiter such operation. 7

Other objects, and the nature of the invention, will more fully appear from a description of an illustrative apparatus embodying the principles of the invention for the purposes vof which description reference should be had to the accompanying drawings forming apart hereof and in which: I

Figure 1 is a centra'l sectional view of the complete mechanism.

Fig. 2 is a detail sectional view of the ratchet taken on the line 22 of Fig. 1.

Fig. 3 is a detail sectional view of the stop mechanism taken on the'line 3-3 of Fig. 1.

Fig. 4 is a sectional view taken on the line 44 of Fig. 1, but showing the cam and switch in squib firing position.

Fig. 5 is a sectional view-showing the spring motor taken on the line 5--5 of Fig. 1.

Fig. 6 is a central sectional view of the protective cover.

Fig, 7 is a view of the indicator disk taken on the line of Fig. 1.

A spring motor 5 drives agenerator B through suitable.gearingtoprovide a current for igniting a set of squibs. The spring motor comprises two similar spiral springs I and 8,*the outer ends of which are anchored on a transverse pin '9,'Fig. 5, fixed in the casing and the inner ends of which are anchored in a slot ID in a driven shaft I'l "rotatable in ball'bearings l2 and I 3. As a safety provision, each spring is strong enough to provide the necessary power for operation whereby any accidental failure of one spring will not make the device inoperative. A washer M separates the two springs. When the spring motor drives shaft H, gear l5 keyed thereon drives pinion I6 secured to or formedon generator drive shaft l1 rotatably supported in a ball bearing I8 in the casing and on the ball bearing IS on the end of the generator shaft 29. The generator shaft, with the generator rotor "6 rigidly secured'thereto, is carried inballbearings 21, '22 and driven through an overrun-ning clutch 23. The overrunning clutch permits winding of the spring motor without turning the generator rotor and permits free overrunning of the generator -rotor after operation of the device. By this arrangement, no great strain is applied to the spring motor or other parts of the mechanism when after operation certain parts are stopped at the point of complete unwinding of the spring motor.

To wind the spring motor, shaft I! is turned by hand wheel 25 on shaft 2 6 while in its outermost position as pressed outward by a spring 21 compressed between the hand wheel and the casing at 28 where" the shaft 26 extends through the casing.

Shaft 26 is formed to providea ratchet wheel 29 and a clutch member '30. The ratchet teeth are engaged by pawl 3| to prevent reverse rotation o'f the shaft and arelong enough to be engaged thereby in all positions of the longitudinal movement of the shaft; The clutch element "31] engages the clutch element '32 formed on the outer end'ofihe'driveshaft ['1 when, but only when, the hand wheelisin its outer-most position. The clutch :elementsas shown are hexagonal. When engaged, the'clutch connects the shafts 'for Winding ofthe spring motor and also ciated parts. The spring motor then drives the generator to cause ignition of the squibs.

Preferably the hand wheel is protected by cover 36, hinged at 31 to prevent operation of the device by accidental pressure on the hand wheel.

A signal device is provided to indicate the fully wound condition of the spring motor and to provide a warning signal if the spring motor is not fully wound and ready for operation. As shown, a disc 49 secured on the end of the shaft H, is visible through a window 4| in the casing. When the spring motor is fully wound a green or white portion 42, Fig. '7, of the disc registers with the window, thus indicating that the device is in condition for operation. In any other position a red portion of the disc is visible. The collar 43 securing the disc on the shaft also reinforces the slotted shaft H at its outer end.

A limiting device is provided to prevent overwinding of the spring motor while permitting more than one complete rotation of the shaft 1 I and gear I 5. As shown, a pin 45 projecting from the side of the gear 15 will engage, during the first part of the winding operation, an arm 46 rotatable upon the shaft II and turn it until it comes against a stop 41, Fig. 3, fixed in the easing. The spring motor is then fully wound. When the device is operated, pin 45 moves away from the arm 46 and after nearly a complete rotation of shaft II engages the other side of the arm and can still rotate a considerable part of a second turn.

Switch mechanism is provided automatically to connect the generator to the work circuit for emergency operation and after operation to again disconnect the generator from the work circuit. Actuall in the ap aratus for which the invention was more particularly developed the switch 50, Fig. 4, in normal position connects a battery to the work circuit but in its emergency position as act ated by the cam 5| it disconnects the battery and connects the generator to the same work circ it for the emergency operation. After the operation is complete the cam causes the switch again to connect the battery to the work circuit. The switch 55 and the cam 5| are best shown in Fig. 4. When the spring motor is fully wound and the device is readv for action, the follower 52 of the switch is on the low part of the cam and the work circuit is connected to the battery and not to the enerator. As the spring motor is released and starts to rotate the cam, the high portion of the cam engages the follower causing the switch to disconnect the battery from the work circuit and to connect the generator thereto for a sufficient period of time for operation. Further rotation of the cam disconnects the generator and restores the connection between the work circuit and the battery. It is to be noted that during the start, and the operation of the spring motor through a predetermined angle, the generator circuit is open and therefore there is no load on the generator to resist a quick pick-up.

The design of the springs 1, 8 is such that failure of either spring is extremely unlikely, however, if failure occurs it will probably occur near the inner end and the broken spring will expand within the drum and assume a position such that the rotation of the shaft II will not be obstructed thereby.

Each spring is of sufficient strength to alone drive the generator and produce the necessary voltage. This provides a safety feature for effective operation even in the event of failure of one spring.

The description of a particular embodiment of the invention is for the purposes of illustration and is not intended as defining the limits of the invention.

I claim:

1. A spring powered electric impulse generator of the character described comprising in com bination a spring motor having dual springs jointly independently capable of operation; a shaft driven by said spring motor; an electric generator having a shaft to be driven; gearing connecting said shafts for operating said generator from said spring motor; an overrunning clutch between said generator and its shaft to permit of winding said spring motor without turning said generator; a clutch associated with said gearing to permit winding of said spring motor in one position and rotation of said generator by said spring motor in another position; an operating shaft for said clutch; a spring loaded winding knob on said operating shaft adapted in one position when pressed against its spring loading to establish rotation of said generator from said spring motor, and in another position when spring loaded to its fullest extent to permit winding of said spring motor; a switch normally disconnecting said generator from a work circuit: and a cam mounted to be operated by release of said spring motor to connect generator in said work circuit, whereby said generator can apply an impulse thereto.

2. A spring powered eectric impulse generator of the character described comprising in combination a spring motor: a shaft driven by said spring motor; an electric generator having a shaft to be driven; gearing connecting said shafts for operating said gener tor from said spring motor; an overrunning clutch between said generator and its shaft to permit of winding said spring motor without turning said generator; a cl tch associated with said gearing to permit winding of said s ring motor in one position and rotation of said generator by said spring motor in another position: an operating shaft for said clutch: a winding knob on said operating shaft adapted in one position to establish rotation of said generator from said spring motor, and in another position to permit winding of said spring motor; a switch normally disconnecting said generator from a work c rcuit; and a cam mounted to be operated by release of said spring motor to connect said generator in said work circuit. whereby said generator can apply an impulse thereto.

3. As an emergency unit for the purposes de scribed, a spring powered. electric impulse generator comprising in combination within a casing; a spring motor mounted within said casing: a rotatable shaft driven by said spring motor; a gear on said shaft: an electric generator mounted in said casing; a driving shaft therefor having a gear meshing with said first gear: an overrunning clutch between said driving shaft and generator to permit of winding up said spring motor in one direction without rotating said generator; a winding stem engageable at will to operatively rotate said driving shaft to wind said spring motor and spring urged into such winding position; a ratchet on said winding stem to hold said spring motor in such wound position; a bore in said casing for slidingly supporting said winding stem; an operating knob external of said casing and operatively connected with said winding stem to slide this inwardly of the casing in its bore against said spring urging to a position to release said clutch and said ratchet and cause said spring motor to rotate said generator, to generate an impulse thereby; a cutout switch in the output circuit of said generator; and a cam mounted to move with said spring motor operating said switch to cut-out said generator when said spring motor is either fully wound or not wound at all and cut-in said generator when said clutch and ratchet are released, to cause said spring motor to drive said generator.

4. An emergency unit as claimed in claim 3 provided with an indicating device having indicia by the spring motor to occupy a preselected posi- I Number REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Name Date 1,205,885 Greby Nov. 21, 1916 1,363,585 Haddow Dec/28, 1920 1,479,152 Myers Jan. 1, 1924 ,803,929 Zaidan May 5, 1931 2,322,067 Soreny June 15, 1943 

